import java.util.LinkedList;
import java.util.Queue;

/**
 * Created with IntelliJ IDEA.
 * Description:
 * User: 26727
 * Date: 2024-10-02
 * Time: 16:16
 */
class Solution16 {
    int m,n;
    int[] dx = {0,0,1,-1};
    int[] dy = {1,-1,0,0};
    public int numEnclaves(int[][] grid) {
        m = grid.length;
        n = grid[0].length;
        boolean[][] vis = new boolean[m][n];
        Queue<int[]> q = new LinkedList<>();
        for(int i = 0; i < m; i++) {
            for(int j = 0; j < n; j++) {
                if(i == 0 || i == m-1 || j == 0 || j == n-1) {
                    if(grid[i][j] == 1) {
                        q.add(new int[]{i,j});
                        vis[i][j] = true;
                    }
                }
            }
        }

        while(!q.isEmpty()) {
            int[] t = q.poll();
            int a = t[0], b = t[1];
            for(int k = 0; k < 4; k++) {
                int x = a+dx[k], y = b+dy[k];
                if(x >= 0 && x < m && y >= 0 && y < n && grid[x][y] == 1 && !vis[x][y]) {
                    q.add(new int[]{x,y});
                    vis[x][y] = true;
                }
            }
        }
        int count = 0;
        for(int i = 0; i < m; i++) {
            for(int j = 0; j < n; j++) {
                if(grid[i][j] == 1 && vis[i][j] == false) {
                    count++;
                }
            }
        }
        return count;
    }
}
